Method of moistening copying-paper.



No. 643,234. Patented Fe'b. I3, I900. F. G. J. POST.

METHOD OF MOISTENING COPYING PAPER.

(Application filed Mar. 21, 1899.:

(No Model.)

NIE STATES PATENT OFFICE.

FRIEDRICH GUSTAV JULIUS PO ST, OF HAMBURG, GERMAN Y.

METHOD OF MOISTENING COPYING-PAPER.

SPECIFICATION formingpart of Letters Patent N 0. 643,234, dated February13, 1900.

Application filed March 21, 1899. erial No. 709,943. (No specimens.)

T0 ctZZ whom it may concern/.-

Be it known that I, FRIEDRICH GUSTAV JULIUS POST, a subject of theGerman Emperor, and a resident of Hamburg, in the German Empire, haveinvented a Method of Moistening Copying-Paper for Use inCopying-Presses, of which the following is a specification.

This invention has relation to the preparation of copying or tissuepaper so that it may be used in the copying-press.

In copying manuscript and other matter prepared with a soluble ink ithas generally been the practice to use sheets of absorbent materialwhich after immersion in Water are subjected to pressure to removeexcess of water to prevent the ink of the subject-matter to be copiedfrom spreading, or what is usually termed running, the result of whichis an illegible or more or less illegible original and copy. Thedifficulty in obtain ing a so-called pad holding just sufficientmoisture to produce a clear copy and leave the original undefaced iswell known, and this is also coupled with quite an amount of labor andthe exercise of considerable j udgment,,acquired by practice only.Furthermore, these pads require moistening at frequent intervals, asthey dry out rapidly. The moistening of the tissue-paper itself by meansof a brush has now been practically abandoned, owing to the difficultyin obtaining a uniformly-moistened sheet containing just sufficientmoisture to obtain a clear copy and leave the original uninjured.

My invention has for its object a method whereby the preparation oftissue or copying paper for the press is greatly facilitated and alldanger of sursaturation practically avoided and whereby a supply ofprepared paper sufficient for obtaining great numbers of copies may behad in a very compact form.

In carrying out myinvention I wind a web of tissue-paper of the requiredtensile strength to be unwound when wet without tearing into a compactroll, the winding being preferably effected under pressure. Inasmuch asthe capacity for absorbing water by paper wound into aroll depends uponthe pressure under which the paper is wound-71. a, the compactness ofthe roll-the amount of water to be used can readily be determined orregulated, so that s'ursaturation can be effectually avoided; hence alsothe necessity of removing excess of moisture before use. The roll oftissue or copying paper may then be immersed in water, or the absorptionof the Water may be expedited by Winding the tissue on a tubularperforated mandrel, immersing said roll in a body of water and applyingsuction to the mandrel to form apartial vacuum therein, and thus drawthe wa ter through the layers of tissue. I prefer, however, to partlyimmerse the roll of tissue in a body of water of greater volume than isactually required to moisten the roll of tissue to the required degree,so that after absoption by the tissue of the desired or requiredquantity of water the level of the latter will be lowered to such anextent as no longer to be in contact with the roll. Immediately afterthe desired quantity of water has been absorbed the outer convolutionsof the roll will contain a greater amount of moisture than is necessary,while the inner convolutions will not contain sufficient moisture, butthe excess of moisture in said outer convolutions will then be graduallyabsorbed by the inner convolutions until the moisture is uniformlydistributed throughout the convolutions, as will be readily understood.In these operations the roll is preferably revolved. Furthermore, with aview to obtaining manifold copies a plurality of webs of tissue orcopying paper may be simultaneously wound into a roll and moistened, asdescribed, and then unrolled simultaneously, as will be readilyunderstood.

To prevent the outer convolutions of the roll from puckering and frombecoming too soft by reason of sursaturation and thus readily separatingand tearing from the roll, I envelop the same in a fabric capable ofabsorbing and holding considerable moisture-as, for instance, a sheet offelt or the like--this .being also of advantage where a number of rollsof tissue are prepared for future use, thus preventing evaporation ofthe water from the outer convolutions.

In the accompanying drawings Ihave shown in Figures 1, 2, and 3 byvertical sectional Views various means for moistening the rolls oftissue.

The apparatus consists, essentially, of a suitable vessel 0, providedwith forked bear- --ings g for thejournals of the mandrel b of the rollof tissue a.

,7 the roll is removed.

As shown in Fig. 1, the roll of tissue a may this case tubular andperforated and closed at one end, .its open end being connected with apipe fiextending outside of the vessel 0 through a suitable stuffing-boxand-provided with a stop cock f, said pipefbeing connected with asuction-pump 2'. 1

As hereinbefore stated, the preferred mode of moistening tissue in theroll is to partly immerse the same in a body of water, as shown in Fig.2, so that after absorption of a certain quantity of the water the levelthereof will sink below and out of contact with the roll. These rolls ofmoistened tissue are for use preferably transferred to a casing adaptedto be closed and to be arranged in proper relation to the copying-press,the casing being prolatter in contact with water until a given quan-'tity thereof has been absorbed, removing the roll from contact with thewater and allowing the inner convolutions of tissue-paper to absorb theexcess of water in the outer convolutions, for the purpose set forth.

2. The mode of preparing tissue-paper for copying purposes,whichconsists in compactly winding a plurality of webs of such simultaneouslyinto a roll, placing the latter in contact with Water until a givenquantity thereof has been absorbed, removing the roll from the water andallowing the inner convolutions of tissue to absorb the'excess of waterin the outer convolutions, for the purpose set forth. 1

8. The mode of preparing tissue-paper for copying purposes,whichconsists in winding -a web of such into a compact'roll, enveloping thelatter in an absorbent fabric and placing the roll in contact with wateruntil a suitable quantity thereof has been absorbed by said fabric andtissue, for the purpose set forth.

4. The mode of preparing tissue-paperfor copying purp0ses,which consistsin compactly winding a web of such into a roll, placing the same into abody of water so that when a given quantity thereof has been absorbeditslevel will be so changed as no longer to be in contact with the roll,and allowing the inner convol utions of tissue-paper to absorb theexcess of water in the outer convolutions, for the purpose set forth.

FRIEDRICH GUSTAV JULIUS lOSl.

Witnesses:

ALEXANDER SPEOHT, E. H. L. MUMMENHOFF.

